Synthesis gas, which is also known as syngas, is a mixture of gases comprising carbon monoxide (CO) and hydrogen (H2). Generally, syngas may be produced from any carbonaceous material. In particular, biomass such as agricultural wastes, forest products, grasses, and other cellulosic material may be converted to syngas.
Syngas is a platform intermediate in the chemical and biorefining industries and has a vast number of uses. Syngas can be converted into alkanes, olefins, oxygenates, and alcohols such as ethanol. These chemicals can be blended into, or used directly as, diesel fuel, gasoline, and other liquid fuels. Syngas can also be directly combusted to produce heat and power. The substitution of alcohols in place of petroleum-based fuels and fuel additives can be particularly environmentally friendly when the alcohols are produced from feed materials other than fossil fuels.
Improved methods and apparatus are needed to more cost-effectively produce syngas. Methods and apparatus are also desired for producing syngas at a greater purity and with desirable ratios of H2 to CO to facilitate the conversion of syngas to other products, such as ethanol. Additionally, improved methods and apparatus to produce alcohols, such as ethanol, from syngas are needed commercially.